Box mill and cutter therefor



' Sept, 22,'1942 R. E. s :H :nr\1BERGER` 2,296,688

VBOX MILL AND CUTTER THEREFOR #ned March 2o, 1941 Patented Sept. 22, 1942 2,296,688 BOX MILL AND CUTTER THEREFOR Robert E. Schoenberger, Shaker Heights, Ohio, assignor to The W. J. Schoenberger Company, Cleveland, Ohio, a corporation of Ohio Application March 20, 1941, Serial No. 384,406

9 Claims.

This invention relates to box mills and cutters therefor for use primarily with machines in which the tool rotates and the Work is stationary, but also adaptable for use where the work is rotated.

One of the objects of the invention is the provision of improved means for clamping the cutter securely in the body of the box mill.

Another object is to provide the body with a readily removable work receiving and supporting bushing. y

Another object of the invention is to provide means for adjusting the cutter bodily in a direction substantially at right angles to the direction in which the cutter approaches and engages the work and substantially laterally of the longitudinal axis of the box mill thus adapting the tool for use with work receiving and supporting bushings and work of varying diameters.

A further object of the invention is to eliminate chattering resulting from the loss of Weight on one side of the body caused by the presence of the chip outlet at that side.

Other objects and advantages of the invention will be apparent as the specification isconsidered in connection with the accompanying drawing, in which:

Figure 1 is an end View of the improved box mill;

Figures 2 and 3 are side views of Figure 1;

Figure 4 is a side View of the V-shaped cutter vclamp or block;

Figure 5 is an edge View of the Wedge or cam member;

Figure 6 is a side view of the cutter detached;

Figure '7 is an end View showing the relationship between the cutter and the wedge or cam member;

Figure 8 is an edge view of the cutter detached; and

Figure 9 is a side view of the cutter detached.

Referring more particularly to the drawing wherein like numerals refer to corresponding parts throughout the several views, I denotes the body and 2 the hollow shank of the box mill. The axial bore 3 of the shank 2 is threaded as at 4 for convenient attachment to the actuating f spindle or head of a machine for reciprocatory and rotary .movement respectively, toward and with respect to the work (not shown) The body portion I is cored to provide a chamber 5 for the accommodation of a drill 6 and a work supporting bushing 1, the latter seating upon a shoulder 8 and being held in place and locked against turning movement by a set screw 9 and a dowel pin I0 respectively. yThe drill 6 seats in a split bushing or collar I I in turn tightly received in a small axial bore I2 communicating at opposite ends with the shank bore 3 and chamber 5. A set screw I3, mounted in a threaded cross bore I4, in the body I of the box mill holds the split bushing and the drill in place.

The outer end face of the bushing 'I is beveled to correspond with the adjacent beveled end face of thel body I, thus adapting the box mill for use in close quarters which is essential Where the box mill is used on an automatic machine having a plurality of closely arranged chucks.

One side of the body I is well as one side of the conical bushing I is cut away to provide a chip clearance space or outlet I5 and a substantially Wedge-shaped space I6 respectively, the latter being adapted to receive a correspondingly shaped clamp or block I1, and the chip space I5 being in open communication with the chamber 5 and bore I2. This clamp functions to securely hold a cutter I8 in operative or cutting position. The cutter is slidably mounted in a groove I9, extending tangentially with respect to the bushing and opening laterally into the wedge shaped space I6. The cutter is adapted to abut with its iiat inner cutting end against a substantially radially disposed flange or wall 20, when the cutter has been forced inwardly to the limit of its movement in that direction. One smooth face 2I of the clamp block II also seats against the flange 20, the latter forming one side wall of the substantially V-shaped opening I6, and the other smooth face 22 of the block Il, is formed with a knurled portion 23, which engages the knurled side 24 of the cutter I8. Feet 25, formed on the face 22 of the clamp block remote from the knurled portion 23, engage the other side wall 26 of the V-shaped space or opening IB. The face 22 of clamp block is drawn into tight clamping engagement with cutter I8 and wall 26 of opening I6, by means of a long screw 21, extending loosely through an opening or recess 23, formed in the body I and having threaded engagement with a registering threaded opening 29 in the block I'I. A short screw 30 rotatably mounted in an opening or recess 3|, formed in the block I'I and having threaded engagement with a registering threaded opening 32, extending laterally through the flange or wall 20, draws the block I'I tightly against the wall or ange 20 and locks the block against outward movement. It is to be noted that the pull exerted upon the block by the long screw 2'I is substantially at right angles to the pressure exerted by the short screw 30, thus securely clamping the cutter against movement under the stress of outward pressure exerted thereagainst by the work. As the corrugations 23 and 24 of the opposing parts I1 and I8 are arranged at a common angle the interlocking effect of these corrugations prevents any slipping of the cutter in its groove I9.

The drill 6 is employed to drill or partly drill an opening or passageway in a tting such as a pipe coupling held in a chuck or work holder, not shown, while the cutter I8 reduces and shapes a portion of the fitting which is subsequently threaded at another station or in another machine. The fittings just referred to by way of example, may vary in size and consequently it is necessary that the work supporting bushing 1 be replaced from time to time by one having a larger or a smaller work receiving opening 33,- according to the diameter of the work being cut and drilled. This can readily be accomplished by removing the set screw 9. It will of course be understood that as the rotating box mill I is moved toward the stationary work the latter enters or is received within the opening 33, in the bushing 1, where it is guided and supported during the working and return stroke of the tool.

The cutter groove I9 is preferably so placed or formed with relation to the diameter of bushing opening 33 that the cutter I8 is adapted to operate on work of a given minimum diameter, and in order to compensate for work of larger diameter, means is provided for bodily moving the cutter sidewise partially out of its groove towards and partially into the V-shaped opening I6 or in a direction parallel with that of the wall or flange 20. Thus a cam or wedge member 34 is slidably mounted upon the wall 42 of the cutter' groove I9 to one side of the cutter and between the latter and side wall 35 of the groove. This side wall is inclined oppositely to the beveled or inclined face 3S of the wedge or cam member 34 which has snug sliding contact therewith. The opposite face 43 of the wedge member has interlocking sliding contact with the adjacent face of the cutter, all as best seen in Figures 2, and '1. An adjusting screw 31 threadedly mounted in the body I, has an enlarged head 38 adapted to engage a shoulder 39 formed on the wedge or cam face 36 of the cam member 34.

When the screw 31 is appropriately turned to .move the cam member 34 inwardly and in a direction substantially parallel with respect t0 the wall 35 of the cutter groove I9, the cutter will be forced sidewise away from or in a direction substantially at right angles to the plane of the cutter groove. The cutting edge of the cutter is thus moved in a sidewise direction away from the axis of the bushing 'I and the work so that when the bushing 1 is replaced by one of larger diameter, the tool will be in a position to operate on work of correspondingly increased diameter, However during this adjustment the cutter cannot be moved inwardly or longitudinally of the cutter groove beyond the face of the wall 2l) against which the inner end of the cutter abuts, because the wall 20 is a fixed part of the body. This is important because the wall 20 serves to accurately and permanently position the cutter with respect to the work so that the latter will be engaged `by the cutter slightly behind its center line, say one thirty second (g1-2) of an inch in accordance with well accepted practice. It will also be noted that the cutter engages the work just before the stock reaches or enters the bushing, in other words the extreme edge 4I of the cutter leads the bushing approximately three fourths 0%) of an inch. It will of course be understood that the short screw 39 and the long screw 21, which coact to tightly clamp the cutter against the flange or wall 2D and the side face 43 of the wedge or cam member 34, must be completely and partially unscrewed respectively before this sidewise adjustment of the cutter can be effected.

Applicant has discovered that the loss of weight caused by forming the chip clearance space or outlet I5 resulted in considerable vibration and chattering. To overcome this objection the body I has been cored or cut away at 40 so that opposing portions of the body will be more or less evenly balanced in weight.

Having thus described my invention, what I claim is:

l. A box mill comprising a chambered body portion having a work receiving opening at one end and a shank at the other end, a cutter movable inwardly through said body tangentially of said work receiving opening, a stop member for limiting inward movement of said cutter when cutting position is reached, means for adjusting said cutter in a direction at right angles to said tangential movement, a substantially V-shaped block having a face adjacent the cutter and another face adjacent the stop member, and means for forcing said block into clamping engagement with said cutter and said stop member to lock said cutter in adjusted position.

2. A box mill comprising a chambered body portion having a work receiving opening at one end and a shank at the other end, a cutter movable inwardly through said body tangentially of said work receiving opening, a stop member for limiting inward movement of said cutter when cutting position is reacheds means for adjusting said cutter in a direction at right angles to said tangential movement, a substantially V-shaped block having a face adjacent the cutter and another face adjacent the stop member, a screw for drawing said block into clamping engagement with said cutter and stop member to lock said cutter in adjusted position and screw means for locking said block to said stop member.

3. A box mill comprising a chambered body lportion and a shank, a bushing removably seated in one end of said body and having a work receiving opening communicating with said chamber, a cutter groove in said body open at its ends and one side and extending tangentially of said work receiving opening, a cutter slidably mounted in said groove, a stop member on said body for limitin-g the inward movement o-f the cutter in the groove, and means lfor bodily :moving said cutter laterally -partially out through the open side of said groove and along said stop means to adjust the cutting edge of the cutter away from the axis of the work receiving opening in the bushing.

4. A box mill comprising a chambered body :portion and a shank, a bushing removably seated in one end of said `body and having a work receiving opening communicating with said Vchamber, :a cutter groove in said body open at its ends and one side and extending tangentially of said work receiving opening, a cutter slidably mounted in said groove, a stop member on said `body for limiting the inward movement off the cutter in the groove, means for :bodily moving said cutter laterally lpartially out through the open side of said groove and along said stop means to adjust the cutting edge of the cutter away from the axis of the fwork receiving opening in the bushing and means r.for releasably clamping the cutter in adjusted position.

5. A box mill comprising a cham-bered body portion and a shank, a .bushing removably seated in one end of said body and having a work receiving opening communicating with said chamber, a cutter -groove in said body open at its ends and one side and extending tangentially of said work receiving opening, a cutter slidably mounted in said groove, a stop member on said body for limiting the inward movement of the cutter in the groove, means for bodily moving said cutter laterally Ipartially out through the open side of said groove and along said stop means to adjust the cutting edge of the cutter away from the axis of the Nvork receiving opening in the bushing and means Lfor reclamping the cutter in adjusted position against said rst mentioned means and said stop member.

6. A box mill comprising a body portion `and a shank, said body formed with a central chamber opening through the outer end of the Ibody, a removable bushing seated in said outer end and having a centrally disposed work receiving opening communicating with said chamber, a drill xed in said body axially of said work receiving opening, a substantially V-shaped opening in said .body having a substantially radially disposed wall, a cutter groove in said body opening into 'said V-shaped opening and extending 4tangentially of s-aid bushing opening and at substantially a right angle to said Wall, a cutter in said groove having an end face parallel .with and engaging said Wall, and means for moving said cutter bodily partially out of said cutter groove in a direction parallel to said Wall.

7. A box mill comprising a chambered body portion, a removable bushing at one end of said body having la lwork receiving opening therein, a cutter movable inwardly through said body toward said Work receiving opening, a substantially radial lwall in said .body for limiting inward movement of said cutter, a substantially V- shaped. opening in said body, a wedge shaped block in said opening, said cutter and said block having opposing rou-ghened faces, screw means extending through the body and into said block for bringing said faces into clamping engagement and means -passing through said block and said radial .Wall for locking said block in said substantially V-shaped opening.

8. A box Imill comprising a chambered body portion having a work receiving opening at one end, a cutter movable inwardly through said body tangentially of said work receiving opening, stop means 'for limiting inward movement of said cutter when the latter is moved to .cutting position, a cam block having a plurality of cam faces, means associated 'with said cam block and said body rior initially moving one of said faces against the cutter to clamp the cutter securely in cutting lposition and means for moving the block in a direction substantially at right angles to said initial movement to cause the other face of said block to be clamped against said stop means.

9. A |box mill comprising a chambered body portion having a work receiving opening at one end communicating with the said chamber, a cutter having its cutting end adjacent said opening, a chip outlet space at one side of the body leading from said work receiving opening, and cut away :portions formed in the body at avpoint substantially opposite said chip outlet space to balance the box mill and prevent chattering.

ROBERT E. SCHOENBERGER. 

